


Therianthrope

by Tarlan



Category: Stargate Atlantis
Genre: Alternate Universe, Alternate Universe - Fantasy, Animal Transformation, M/M, Reverse Big Bang Challenge
Language: English
Status: Completed
Published: 2018-10-26
Updated: 2018-10-26
Packaged: 2019-08-07 21:44:53
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,762
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/16416533
Author URL: https://archiveofourown.org/users/Tarlan/pseuds/Tarlan
Summary: Rodney had never truly believed in any myths and legends. A journey to the Lantean mainland with John shows him Atlantis is not the only myth that has a basis in fact, and he has now become a part of those same myths and legends.





	Therianthrope

**Author's Note:**

  * For [Syble](https://archiveofourown.org/users/Syble/gifts).



> SGA Reverse Bang 2018 - Written for [Syble4](https://syble4.dreamwidth.org/) to go with their beautiful artwork.

_**Therianthropy** is the mythological ability of human beings to metamorphose into other animals by means of shapeshifting._

Atlantis was everything Rodney dreamed it would be, from its intricate architecture to the soaring towers that made Earth's fairy tale castles look clunky and ugly in comparison. After an initial panic, wondering if they were all about to die horribly when the shield collapsed, the city rose majestically to the surface, and now it floated on a clear blue ocean. After ten thousand years at the bottom of an alien sea in another galaxy Atlantis was not in the best of shape so Rodney knew he had a lifetime of work ahead of him, but that suited him just fine. This was one of his childhood fantasies come to life. He had loved the stories of a city lost beneath the waves, making it one of the few exceptions to his disinclination towards the soft sciences, in this case myths and legends, but the realist in him had never dreamed he might actually end up on Atlantis.

Near-death experience aside, Rodney had never felt happier. Carson had perfected the ATA gene therapy, giving Rodney the ability to use the Ancient technology better than some of the stronger natural ATA carriers, and not even learning the reason why the ancients abandoned Atlantis - the Wraith - could daunt his spirits. He stretched out on the bed of his assigned quarters; the best he could find to give him easy access to the laboratories and other facilities. As rank did have its privileges it also came with a bathtub and a breathtaking view across the city and the ocean beyond. A few days later, having discovered the 'storage room' in the corridor beyond was actually a transporter, Rodney was even happier with his accommodation as now he didn't have to walk far at all. His quarters were larger than the apartment he had rented in Colorado Springs, though he missed the battered old couch that had molded itself perfectly to his body after years of usage.

Rodney knew it might be a one way trip when he stepped through the Stargate so he had resigned himself to never feeling the butter-soft comfort of that old leather couch again. A shame really, but the few items of Ancient furniture still remaining on Atlantis turned out to have similar properties to his couch, molding to his body. Once more rank had its privileges as he ordered some of his 'minions' to carry one of the Ancient couches into his quarters, and he stretched out on it now to think.

His reverie lasted only a few moments before Sheppard was calling for him over the radio.

"McKay, gear up."

"Gear up? What..?"

"We're heading out."

"Wait! Where could you possibly...?"

"Jumper Bay. Fifteen minutes."

Infuriatingly, Sheppard signed off abruptly and Rodney toyed with the idea of ignoring the 'summons'. He wasn't part of the military so the Major couldn't order him about like one of his Neanderthal goons. Unfortunately, Rodney then started to wonder why the Major had insisted on him 'gearing up', and the more he thought about it, the more he felt his resistance crumbling. He sat up with a snarl. Whether intentional or not the Major had peaked his curiosity and Rodney knew he would not be able to rest until he found out what was going on. As he wasn't sure what Sheppard meant by gear-up he grabbed his jacket and third-best laptop, not wanting to take either of his best laptops off-world in case they got damaged or lost. It was not like he could run down to the nearest tech store and replace them. 

When he reached the Jumper Bay Sheppard was nowhere to be seen but Rodney noticed the back was lowered on one of the Gateships that Sheppard insisted on calling Puddlejumpers. Cautiously he entered.

"Major?"

"Here," came a reply from the front of the Ancient craft, and Rodney moved forward, finding Sheppard sitting in the pilot's seat wearing a military expedition jacket over a black t-shirt. He had rolled up the sleeves to just below his elbows, and for a brief moment Rodney wondered at the significance of the single black wristband. Sheppard indicated towards the co-pilot seat.

"Take a seat, McKay. We're going on a recon."

Sheppard turned away before Rodney could object, pulling up the HUD with ease, but then to someone with a powerful expression of the ATA gene it probably was just a thought. It reminded him how Carson always looked constipated, straining to get things to work, but Rodney was convinced Carson simply tried too hard because he was afraid of the technology as he had noticed how easy it came to Carson when he wasn't consciously thinking about it.

"Jumper One ready to depart," Sheppard stated, flicking a glance towards Rodney; his eyebrows taking on a life of their own as he indicated towards the seat for a second time.

"Retracting the roof. Be careful out there, Major, Doctor McKay," Elizabeth replied, proving this wasn't an unsanctioned mission.

As the Jumper rose smoothly towards the opening ceiling, Rodney sat down. He was still confused, wondering why Sheppard needed him on a simple recon when one of the geologists or biologists would have been a better choice, but that was quickly forgotten as the Jumper cleared the main tower and hovered over the very top of the city. Rodney leaned forward to stare through the cockpit window, awed by the sight of the city spread out below them.

"WOW!" He glanced towards Sheppard, rolling his eyes at the obvious smirk.

Rodney had never got on with any of the military, butting heads with Colonel Sumner almost daily, but for some reason Sheppard seemed to like him. At first he thought it was because he had allowed Sheppard to shoot him in the leg while testing the Ancient personal shield device, but Sheppard had been surprisingly friendly from the moment they met. Rodney had been annoyed at the time when yet another brainless Flyboy turned out to have a natural expression of the ATA gene but all Sheppard had said was, "Cool!", and then made it his life's mission to remind Rodney of his 'special gene' at every opportunity. It hadn't helped knowing John Sheppard was exactly Rodney's type - blond ladies, dark-haired guys. The only thing stopping Rodney from being a gibbering wreck around Sheppard was believing Sheppard had no brains beneath his mop of messy, dark hair. However, some things simply didn't add up so Rodney hacked Sheppard's personnel record only to discover there was no IQ level on file, but just as Rodney suspected, he knew Sheppard's IQ had to be higher than the average soldier after seeing his grades, and in particular the Master's degree in Aeronautical Engineering that Sheppard had never mentioned.

So here was John Sheppard: tall, dark-haired, muscular with a runner's lean body, drop-dead gorgeous... and smart. Rodney was doomed.

Sheppard piloted the Jumper away from the city, heading towards the only land mass on the planet.

"Sheppard? Why am I here?"

Sheppard flicked him a look with animated raised eyebrows. "Because I asked?"

"Ordered."

"Asked," he stressed, before clarifying, "You could have refused, but you didn't."

Rodney opened his mouth to argue but sighed instead as it had not occurred to him that he could refuse, and if he had to be brutally honest with himself, he wasn't sure he would have refused anyway. He liked being around Sheppard. There was something about the man that appealed on a deeper level than just good looks, a decent brain, and a similar love for comic books and science fiction. He had no clue what it was but it was a strength of feeling, of belonging, that made even his greatest crush on Sam Carter pale into insignificance. If Rodney had been one of those soft scientists with a poet's soul he would have insisted they belonged together on the molecular level.

His introspection was broken by Sheppard.

"There. On the horizon."

The Jumper was sweeping towards the only land mass on the planet, and area around the same size as Mexico. The geologists had been begging to go check it out since they arrived in Atlantis. Once Sheppard had done his fly-by survey Rodney would organize a proper expedition to the mainland to appease them. The thin line on the horizon grew quickly and only minutes later they were passing over the shoreline and heading towards the distant mountains. Beneath them lay a verdant green canopy, the land beneath likely untouched by either humans or Ancients in over ten thousand years. From up here it looked like paradise but Rodney was not one to be fooled by nature. There would be bugs, and possibly spiders, or venomous snakes, or man-eating lizards. For all he knew there could be dinosaurs - huge carnivorous creatures that would see him only as a tasty morsel, a snack on two legs rather than the smartest man in two galaxies.

The canopy of trees gave way to a wide valley with a river meandering through it, its water glistening enticingly in the bright sunlight.

"I'm going to set us down near that rock formation."

"Uh... maybe that's not such a great idea. Perhaps we should let the xenobiologists check it out before-"

But Sheppard was already landing the Jumper so gently Rodney wasn't certain if they had touched the ground or if they were still hovering above scant inches it. Sheppard brought up the HUD, checking for any life forms. In the distance was a herd of some kind of creature similar to a horse, except it had six-legs, but even Rodney knew animals tended to herd together for greater protection against predators. When Sheppard lowered the back the warmth from outside swept in, like a pleasant summer's day. Still, it was far too hot for wearing his heavy expedition jacket so Rodney pulled it off, leaving it draped over the co-pilot's seat. He reached across and took the handheld life-form detector from its concealed compartment without conscious thought. he checked the display but there was nothing larger than a field mouse in close proximity.

"There could be anything out there. A T-rex for all we know."

"There's nothing too dangerous out there for us. I already checked it out with the xenobiologists."

"You have?"

"You think I'd bring you out here without guards if I thought it was dangerous? Rodney, even the insects are... mostly harmless."

"Mostly?" Rodney shook his head. "Wait. Then why are we here?"

Sheppard looked a little cagey. "Because I need to show you something. Away from Atlantis."

"Because of the city? I know Atlantis might seem sentient but-."

"No. Because of the people in the city. It's... private." He licked his lips nervously. "Wait here."

"Sheppard? John!" Rodney called out uselessly as Sheppard jogged off towards the closest outcrop, quickly disappearing behind it. Ignoring Sheppard's order to wait, Rodney left the relative safety of the Jumper and began walking towards the outcrop. He was halfway there when the air was filled with a strange sound. Rodney froze, checking the sky above anxiously, torn between retreating back to the Jumper or racing forward to where Sheppard had disappeared, worried as the sound seemed to be coming from that direction.

The creature rose up from behind the rocky outcrop, dark, leathery wings beating the air as it rose higher. The black, man-sized, dragon-like creature turned towards Rodney, swooping towards him. Rodney yelled in shock and ran several steps, freezing when the creature dropped down in front of him, the life signs detector dropping from his hand. His terror gave way to curiosity as it made no attempt to attack and eat him. Slowly Rodney reached down to pick up the life signs detector, grimacing when he noticed the cracked screen. The detector was still working and it indicated two man-sized life-forms, both colored blue - for friendly. Rodney wondered why Sheppard hadn't come running. His breath hitched in fear, wondering if the creature had already filled its belly with John Sheppard. It tilted his head in a strangely familiar way, and that's when Rodney started making the connection. As his mind quieted down from the adrenaline high of fear he felt something pushes at the edges. Random images and feelings that were not his own.

"John?"

[](https://ic.pics.livejournal.com/tarlanx/6659521/1300790/1300790_original.jpg)

The creature dipped its head.

"You're... You're... One of them."

By them he meant a Therianthrope, a human who could transform into an animal, or many different animals in some cases. For most of history these humans had been victimized or made into villains - werewolves, kitsune, skinwalkers, and even a whole tribe called The Jaguar People that was hunted into extinction in the previous century. Carson had said something to him once about enjoying being a turtle, but Rodney thought Carson meant how his life would be less complicated if he was a turtle. The connection came. The ATA gene was only natural in two percent of the human population, running in families for the most part. What if all those with the ATA gene had the ability to transform to a greater or lesser degree?

He recalled the silly bedtime stories his grandma used to spin, of coming from a long line of Selkies and merpeople, humans who could take the form of seals or fish but who could control the change sufficiently to remain part human if needed. Other half-human creatures from myths and legends sprang to mind: centaurs, satyrs, the Sphinx. Perhaps even angels and demons.

He had the ATA gene now, a strong expression despite it not being natural but instead of being horrified at the thought Rodney began to wonder if he could transform now.

"Can I?" he asked John, both aloud and by thought.

The dragon rocked its head, seeming to shrug its shoulders, then before Rodney's eyes it began to grow indistinct. It's black body began to break apart to reveal pink skin underneath. It's leathery wings dropped away, turning to dust in his hand when Rodney tried to pick up a piece. The body rippled as Rodney watched the dragon change back to human form - to John. Embarrassed, Rodney looked away when he realized John was now standing before him naked, though not so quickly he didn't take in the clean lines of his body, feeling a warmth in his belly heading south into his groin. John gave him a fatuous grin, eyes dipping to where Rodney was trying to conceal his physical reaction to John's nakedness.

When John walked away, heading back towards the outcrop, likely to gather up his clothing, Rodney could not resist peeking at the perfection of the view. He waited impatiently while John dressed out of sight deciding to use some of the nervous energy to head back to the Jumper and see if there was any coffee in the picnic hamper he'd spotted earlier on the bench seats in the back. John joined him a few minutes later, accepting the drink as he sat down on the bench seat opposite. 

"So... Have you always been a Therianthrope? Or is this something you only just..." Rodney waved a hand.

"Always. So was my mother, but no one else in the family could..." He waved a hand too. "You know. That I know of."

"Huh! If it's related to the ATA gene then... I've always wanted to be a cat. A domestic cat." Rodney looked hard at John. "How do you..." he waved his hand again.

"Change?" John shrugged. "I just think hard about what I want to be... but I've never tried changing into anything mythical before coming to Atlantis. I figured if Atlantis is real, then maybe some of those other myths are also real."

"I think Carson changes into a turtle," Rodney stated abruptly.

John seemed to bite back on a grin. "Yeah? Cool!"

"Just something he..." He stopped himself from going off on a tangent. "I want to try."

John bit his lower lip nervously. "You'll have to get naked first."

"Oh... I guess that makes sense."

With some alacrity Rodney began to strip, leaving John looking surprised, but Rodney noticed he also looked a little flustered and embarrassed, which was strange as the military usually trained that out of its soldiers, making them share bunkhouses and communal showers. He noticed John was unable to resist checking him out. Rodney knew he wasn't in the best physical shape, mostly due to spending the majority of his time sitting in front of a computer screen rather than hitting the gym, but his previous boyfriends had liked his muscular arms, broad shoulders, and his ass once he'd passed through the skinny man-boy stage in his life. He only wished he could have kept all the blond, curly hair from his youth. Once naked he felt a little embarrassed but John seemed to have got over his own awkwardness, openly admiring him now. At least Rodney had his answer to whether John reciprocated his feelings, if only the lust part of them.

Rodney cleared his throat. "So how do I do this?"

"Put an image in your head of what you want to be. Focus on it, and... let it happen."

Rodney blinked. "There has to be something more than... 'let it happen'," he stated almost derisively but John simply shrugged.

"You over-think things. Just... let go. Let it happen."

Rodney wasn't totally convinced but he closed his eyes and thought about his beloved cat; he had been forced to leave Bailly behind with his neighbor. He missed his cat. Rodney felt something. It wasn't painful but it wasn't comfortable either as his body began to mutate, fur sprouting through his skin in tabby colors, his body becoming more dense as it slowly reduced in size. The scientist part of his brain knew it was a conservation of mass, with the molecules comprising his body moving closer together. He wondered if it was possible to choose an animal so small the density of his body would make it impossible to move. It would explain why most of the myths and legends surrounding Therianthropy concerned human-sized transformations into animals.

Rodney looked down in awe as his fingernails slid back into his skin, becoming retractable like a cat. His hearing seemed to sharpen but his eyesight became fuzzier, less color-filled, and the light outside seemed too bright. He realized he was seeing the world through a cat's eye. Rodney looked across at John as the transformation slowed; he was now looking up at John. Rodney sprang down onto the floor, feeling the heaviness of his limbs from reducing the size of his body. He thought himself a little bigger and felt some of the drag on his body release, aware he was now larger than the average house cat and possibly approaching the size of a Maine Coon. John was sniggering at him, finding it amusing to watch him experiment, so Rodney jumped up beside him, staring hard into hazel eyes and directing a few choice thoughts in John's direction.

He arched his back as John reached out to stroke his fur, relishing the feel of the fingers, surprising himself when he heard a rumbling and knew he was purring. He pushed his head against John for more, purring louder as John obliged.

As much as he wanted to remain this way, he could feel the stronger pull of reverting back to human form. Just as John had stated before, he tried not to over complicate it and just let it happen, feeling the discomfort as his body transformed back leaving him seated too close to John, fully naked. Or perhaps not close enough as John cupped his face and drew him into the sweetest kiss. Rodney spared only a glance as the back of the Jumper raised and the bench seat widened without conscious thought, focused more on John stripping off his clothing until they were both naked, wrapped in each other's arms, still kissing deeper and harder.

Time seemed to slow down as they moved together, John's hand gripping both of them, bringing them both to ecstasy as he gasped out in pleasure. 

Afterwards they lay together with John's head pillowed on Rodney's shoulder, one leg slung over Rodney's thighs, and his arm draped over Rodney's stomach.

"Have you ever done it... in animal form?" Rodney asked.

John raised his head and stared at him in disgust. "Not exactly met many Therianthropes other than my mother... until Atlantis."

Rodney grimaced, realizing what he had implied. "Yes, of course. Sorry."

John snorted and dropped his head back down, and Rodney relaxed again.

"I bet there are a lot of Therianthropes on Atlantis now," he murmured, as Carson's ATA gene therapy had taken with just under fifty percent of the expedition. 

"Only interested in one," John shot back while lazily rubbing his fingers through Rodney's sparse chest hairs, grazing a sensitive nipple.

Rodney knew they would have to head back to Atlantis all too soon, wishing they could stay in this quiet moment with just the two of them wrapped up in each other. He wasn't sure what would happen when they got back but there were no regulations, military or otherwise, that would stop them from staying together; no fraternization rules preventing relationships, not on a one-way trip to another galaxy. Until they found a way to contact Earth they were on their own, a colony. A colony where almost half were no longer wholly human.

They were almost new species on Atlantis, an evolution like the X-Men, or was it a devolution as the Ancients had existed in human form while Homo sapiens was still living in caves, and possibly created by the Ancients in their image. It was a recessive gene becoming dominant after ten thousand years through genetic experimentation. How would it impact on their lives if the expedition never regained contact with Earth, how would it change if they did make contact after a few years, or after a few decades, or not until thousands of years later? He knew these were problems and scenarios for people like Elizabeth to sort through, not scientists like him, except the gene therapy had not taken with Elizabeth. She was a fair person though, a brilliant diplomat so perhaps he was worrying over nothing.

"Stop thinking so hard," John murmured, snuggling against his shoulder. "Sleep."

Rodney smiled, and happily obeyed that order, content to leave the problems of the future for a few more hours.

END  
 


End file.
